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1.
Electricity and hydrogen can be used as energy carriers to reduce emissions of CO2 from small and mobile energy users. One of the most promising technologies for the production of electricity and hydrogen with low CO2 emissions is coal gasification with CO2 capture and storage. Performance and cost data are presented for plants which produce electricity and hydrogen alone and plants which co-produce both of these energy carriers. The co-production plants include plants which produce a fixed ratio of hydrogen to electricity and plants which are able to vary the ratio while continuing to operate the gasification and CO2 capture parts of the plant at full load. The paper also assesses the ability of these types of plants to satisfy the varying demands for hydrogen and electricity in future energy supply systems. The lowest cost option for the scenarios assessed in the paper is the use of flexible co-production plants with underground buffer storage of hydrogen.  相似文献   

2.
We present a GIS method to interpret qualitatively expressed socio-economic scenarios in quantitative map-based terms. (i) We built scenarios using local stakeholders and experts to define how major land cover classes may change under different sets of drivers; (ii) we formalized these as spatially explicit rules, for example agriculture can only occur on certain soil types; (iii) we created a future land cover map which can then be used to model ecosystem services. We illustrate this for carbon storage in the Eastern Arc Mountains of Tanzania using two scenarios: the first based on sustainable development, the second based on 'business as usual' with continued forest-woodland degradation and poor protection of existing forest reserves. Between 2000 and 2025 4% of carbon stocks were lost under the first scenario compared to a loss of 41% of carbon stocks under the second scenario. Quantifying the impacts of differing future scenarios using the method we document here will be important if payments for ecosystem services are to be used to change policy in order to maintain critical ecosystem services.  相似文献   

3.

Alternative energy balances aimed to mitigate greenhouse gas (GHG) emissions are developed as alternatives to the baseline energy balance. The section of mitigation options is based on the results of the GHG emission inventory for the 1987–1992 period. The energy sector is the main contributor to the total CO2 emissions of Bulgaria. Stationary combustion for heat and electricity production as well as direct end-use combustion amounts to 80% of the total emissions. The parts of the energy network that could have the biggest influence on GHG emission reduction are identified. The potential effects of the following mitigation measures are discussed: rehabilitation of the combustion facilities currently in operation; repowering to natural gas; reduction of losses in thermal and electrical transmission and distribution networks; penetration of new combustion technologies; tariff structure improvement; renewable sources for electricity and heat production; wasteheat utilization; and supply of households with natural gas to substitute for electricity in space heating and cooking. The total available and the achievable potentials are estimated and the implementation barriers are discussed.

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4.
All municipal solid waste (MSW) management systems—even “high quality systems” or those employing “best practices”—face multiple challenges, e.g., decreasing prices of secondary raw materials recovered by municipalities, increasing complexity of waste composition, technological lock-ins. Policy-making involves translating these challenges into goals that are generic in nature and implementing them on MSW fractions thanks to tailor-made policy tools, e.g., anticipated disposal fees. Anticipating the impacts of policies can provide valuable insights into the adequacy of policy tools with respect to economic, political, and social contexts of MSW. The goal of this paper is to construct consistent, future scenarios of Swiss waste glass-packaging disposal based on literature and stakeholder knowledge, including the allocation of waste to different disposal routes. These scenarios are future states to which the current system could transit to due to alternative policies in line with waste policy goals and varying societal constraints (e.g., commodity prices). Results of scenario construction show that policy has a limited effect on waste glass-packaging disposal because of economic constraints, preventing goals from consistently being achieved. For instance, increases in energy prices can impede a policy favoring recycling over downcycling to foam glass, an energy-saving product. The procedure applied to construct possible scenarios suits well the ambition of considering uncertain future developments affecting MSW management as it integrates qualitative and quantitative knowledge of various sources and disciplines.  相似文献   

5.
A debate is still open on issues of waste to energy methodologies aiming to answer to questions of particular relevance, such as whether the concept of SRF/RDF production can be applied directly to MSW through the Mechanical–Biological Treatment (MBT) process, when selective collection acts as a virtual pre-treatment of the same, or if the use of SRF/RDF as alternative fuel in cement kilns is the most sustainable solution. In this study, two scenarios were analyzed and compared: (a) the use of SRF in a new dedicated thermal plant for electricity production and (b) the use of SRF as an alternative fuel in an existing cement plant. The comparative assessment was based on principles of Sustainable Waste Management embracing technical and cost issues, environmental protection, industrial ecology and symbiosis. The application of SWOT analysis showed that the use of SRF in cement kilns is more sustainable compared to its use in a new dedicated plant for electricity production.  相似文献   

6.
Waste reduction was recognised as the main goal of waste management policy in the EU in the 1990s. Although knowledge of past waste generation is essential for effective waste reduction policy there are no comprehensive statistics on the past development of municipal solid waste (MSW) production. MSW management is currently under turmoil in many EU countries as the requirements of the EC landfill directive (1999/31/EC) are set into force. In this study, the production and composition of MSW in Finland between 1960 and 2002 is presented using historical data. The impact of population, affluence and technology on MSW production are analysed using the IPAT equation and three scenarios are constructed until year 2020. The results are compared with national future targets on MSW production. Production of MSW increased in Finland until 1990, declined to year 1997, increased to 2000 and then declined again. The share of organic and plastic waste increased over the study period while the share of paper and cardboard declined. The results suggest that so far national targets on MSW reduction have been set fairly low. Moreover, our scenarios depict a wide range of future MSW production, even though the time horizon is not longer than 15 years into the future. In order to narrow this range, continuous improvement of the statistics of MSW is essential.  相似文献   

7.
We compare calculated greenhouse gas emissions for a North American beef feedlot operation, which includes biogas production by anaerobic digestion with subsequent electricity generation (the AD case), to the emissions for a “business as usual” case, which includes both a feedlot and an equivalent amount of grid-generated electricity. Anaerobic digestion, biogas production and electricity production are the major sources of differences in emissions. Fertilizer production, crop production, manure collection and spreading, as well as the associated transport stages are also considered within the LCA system boundaries; impacts on life cycle emissions from these sources are lower. Running a feedlot and producing electricity using typical grid power plants produces 3,845 kg CO2?eq/MWh while running a feedlot, which generates biogas to produce electricity, produces 2,965 kg CO2?eq/MWh. This savings of 880 kg CO2?eq/MWh arises because the net power generation in the AD case emits about 90% less life cycle GHG emissions compared to grid-average electricity. The high overall emission levels arise due to emissions associated with enteric fermentation in beef cattle as the main source of GHG emissions in both the “business as usual” and the AD cases. It contributed 57% of total emissions for the feedlot /biogas /electricity system and 44% of total emissions for the feedlot /grid electricity system.  相似文献   

8.
9.
At a time when future sources of energy are under close scrutiny, both in terms of availability and suitability, geothermal energy ranks among the candidates for inclusion in any appraisal of alternative forms of supply. The use of geothermal energy for the production of electricity and for supplying domestic and industrial heat is a comparatively recent phenomenon, and its application remains closely constrained by favourable geological conditions. Yet exploration in several countries shows that geothermal energy may emerge as an important adjunct to total energy supply in many localities. McNitt outlines some of the economic and technological parameters of this energy source. Small scale geothermal power stations are more economic and less capital intensive than conventional plants, which make them of particular interest for developing countries with small electricity systems and competing demands on limited capital resources. The principal capital expenditures in the development of geothermal sources include exploration, steam production, installation of generating plant and the cost of effluent disposal. The wider use of low grade geothermal heat is also examined, in addition to the environmental problems occurring to the development of geothermal energy. The scope for technical co-operation in the development of geothermal energy is substantial, and it is likely that this source of energy will undergo more intensive development on the local scale in the future.  相似文献   

10.
The General Agreement on Trade in Services (GATS) seeks to expand international trade in a wide range of services ranging from tourism to telecommunications and education. In recent years, it has come under attack from civil society organizations in both the North and the South for having a detrimental impact on poor people's right to basic services. This article explores some of these controversies, using the example of water services. It focuses specifically on the impact of the GATS on poor people's right to water and national governments’ ability to safeguard the interests of poor people through regulation. It demonstrates that, de jure, the liberalization of water‐related services under the GATS may not necessarily undermine the ability of governments to introduce the kind of legislative measures necessary to realize poor people's right to water. Still, de facto, the exercise of policy autonomy might be substantially curtailed due to inherent ambiguities in treaty interpretation, the politics of process arising out of power asymmetries, a lack of transparency in processes of negotiation as well as institutional and other deficiencies in the domestic politics of WTO member states.  相似文献   

11.
Complex relationships exist between programs to reduce carbon dioxide (CO2) from the electricity sector and programs to promote renewable electricity generation. Simulation modeling of three scenarios in the UK electricity sector are used to identify potential interactions between these programs. A strict CO2 cap can result in a renewable electricity requirement being easily met. Conversely, the renewables quota could be required under low natural gas prices to keep electricity suppliers from switching from coal to gas. Similarly, CO2 trading can reduce renewables deployment levels because purchased CO2 allowances replace renewables. Therefore, both programs are required to ensure CO2 and renewables goals. The planning implications for administrative procedures and renewables subsidies are also discussed.  相似文献   

12.
This article presents a historical analysis of the power generation choices in Zimbabwe since independence in 1980; their causes and consequences. In the early 1980s, the electricity supply choices of the country were dictated by a policy of self-sufficiency, and least-cost supply options (e.g. imports and hydropower) were rejected at a not negligible economic cost. At the end of the 1980s, a new political environment and pressures from the World Bank prompted substantial changes towards least-cost alternatives. In the early 1990s, security of supply motives still played an important role and financial constraints were severe. At present, however, there is little evidence that imported power is still as cheap a source of electricity as it was about 15 years ago. This situation together with the ongoing trend towards higher discount rates imply that thermal power, in particular coal-fired power, will dominate future electricity supply investments in Zimbabwe.  相似文献   

13.
ABSTRACT: This paper describes the formulation and application of a ground-water hydraulic management model to determine the optimal development and operating policies of a regional aquifer in the Eastern Province of Saudi Arabia. The hydraulic response of the aquifer system is represented by a simulation model that is linked to an optimization management model using response functions. Yearly optimal ground-water extraction rates over a planning horizon of 15 years are determined for four scenarios, each reflecting alternative ground-water development policies. The results are presented in the form of tradeoff curves, relating drawdowns to optimal pumpage, which may enhance the decisionmaker's ability to select the best development policy from a set of alternatives. The results illustrate how various optimal management schemes can be devised to increase the total withdrawal from the aquifer while preventing excessive de-watering.  相似文献   

14.
Better insight in the possible range of future N?O emissions can help to construct mitigation and adaptation strategies and to adapt land use planning and management to climate objectives. The Dutch fen meadow landscape is a hotspot of N?O emission due to high nitrogen inputs combined with moist peat soils due to land use change. Socio-economic developments in the area are expected to have major impacts on N?O emission. The goals of this study are to estimate changes in N?O emissions for the period 2006-2040 under three different scenarios for the Dutch fen meadow landscape (rural production, rural fragmentation, and rural multifunctionality) and to quantify the share of different emission sources. Three scenarios were constructed and quantified based on the Story-And-Simulation approach. The rural production and the rural fragmentation scenarios are characterized by globalization and a market-oriented economy; in the rural production scenario dairy farming has a strong competitive position in the study region, while under the rural fragmentation scenario agriculture is declining. Under the rural multifunctionality scenario, the global context is characterized by regionalization and stronger regulation toward environmental issues. The N?O emission decreased between 2006 and 2040 under all scenarios. Under the rural production scenario, the N?O emission decreased by 7%. Due to measures to limit peat mineralization and policies to reduce agricultural emissions, the rural multifunctionality scenario showed the largest decrease in N?O emissions (44%). Under the rural fragmentation scenario, in which the dairy farming sector is diminished, the emission decreased by 33%. Compared to other uncertainties involved in N?O emission estimates, the uncertainty due to possible future land use change is relatively large and assuming a constant emission with time is therefore not appropriate.  相似文献   

15.
The Finnish anthropogenic CH4 emissions in 1990 are estimated to be about 250 Gg, with an uncertainty range extending from 160 to 440 Gg. The most important sources are landfills and animal husbandry. The N2O emissions, which come mainly from agriculture and the nitric acid industry are about 20 Gg in 1990 (uncertainty range 10–30 Gg). The development of the emissions to the year 2010 is reviewed in two scenarios: the base and the reduction scenarios.According to the base scenario, the Finnish CH4 emissions will decrease in the near future. Emissions from landfills, energy production, and transportation will decrease because of already decided and partly realized volume and technical changes in these sectors. The average reduction potential of 50%, as assumed in the reduction scenario, is considered achievable.N2O emissions, on the other hand, are expected to increase as emissions from energy production and transportation will grow due to an increasing use of fluidized bed boilers and catalytic converters in cars. The average reduction potential of 50%, as assumed in the reduction scenario, is optimistic.Anthropogenic CH4 and N2O emissions presently cause about 30% of the direct radiative forcing due to Finnish anthropogenic greenhouse gas emissions. This share would be even larger if the indirect impacts of CH4 were included. The contribution of CH4 can be controlled due to its relatively short atmospheric lifetime and due to the existing emission reduction potential. Nitrous oxide has a long atmospheric lifetime and its emission control possiblities are limited consequently, the greenhouse impact of N2O seems to be increasing even if the emissions were limited somehow.  相似文献   

16.
This paper studies how fisheries services are classified in the World Trade Organization (WTO) framework for trade in services and discusses the potential impact of unclear classifications. The WTO plays a key role in regulation and assessment in the area of trade in services, mainly due to the General Agreement on Trade in Services (GATS), which contains the only set of multilateral rules managing such trade internationally. The purpose of GATS is to create a credible and reliable system of international trade rules that ensures fair treatment of all participants. Through negotiations, individual countries establish commitments to provide market access and limiting national treatment in various service sectors. During such negotiations, the classification of services is a prerequisite to ensure unambiguous and comparable commitments. However, the classification list used by the WTO, namely the W/120, is based on, and corresponds to, old versions of other classification lists, leading to unclear classifications. This lack of clarity in sectoral classifications makes policy analysis unnecessarily difficult and creates a risk that trade agreements may be interpreted differently by different parties.  相似文献   

17.
To achieve water quality goals and wastewater treatment cost optimisation in a river basin, a water quality management model has been developed through the integration of a genetic algorithm (GA) and a mathematical water quality model. The developed model has been applied to the Youngsan River, where water quality has decreased due to heavy pollutant loads from Kwangju City and surrounding areas. Pollution source, land use, geographic features and measured water quality data of the river basin were incorporated into the Arc/View geographic information system database. With the database, the management model calculated treatment type and treatment cost for each wastewater treatment plant in the river basin. Until now, wastewater treatment policy for polluted rivers in Korea has been, first of all, to construct secondary treatment plants for untreated areas, and secondarily, to construct advanced treatment plants for the river sections whose water quality is impaired and for which the water quality goal of the Ministry of Environment is not met. Four scenarios that do not use the GA were proposed and they were compared with the results of the management model using the GA. It became clear that the results based on the GA were much better than those for the other four scenarios from the viewpoint of the achievement of water quality goals and cost optimisation.  相似文献   

18.
Abstract

This study examined trends in population redistribution and residential land use changes in northeast Scotland during 1988 to 2003. We utilised a geographical information system (GIS) tool to bring together data from interrelated sources and to analyse population settlement and land use changes at detailed spatial scale. This analysis revealed that substantial land conversion had taken place in the region; particularly conversion of agricultural lands to built-up and residential areas. It also drew attention to policy conflicts, discrepancies between policy rhetoric and policy implementations. More specifically, it was shown that substantial farm land conversion had taken place in suburban areas and rural Aberdeenshire with little change in the size of derelict land in Aberdeen City. The reason given for this was that it was costly to rehabilitate and reuse derelict lands and this conflicted with the objective of providing affordable housing in the City region. The implication of this study is that if the declared policy objectives of integrated and sustainable land use and transport policies are to be achieved, then local authorities may need to cooperate to minimise conflicts between economic and environmental objectives.  相似文献   

19.
Emissions from electricity generation will have to be reduced to near-zero to meet targets for reducing overall greenhouse gas emissions. Variable renewable energy sources such as wind will help to achieve this goal but they will have to be used in conjunction with other flexible power plants with low-CO2 emissions. A process which would be well suited to this role would be coal gasification hydrogen production with CCS, underground buffer storage of hydrogen and independent gas turbine power generation. The gasification hydrogen production and CO2 capture and storage equipment could operate at full load and only the power plants would need to operate flexibly and at low load, which would result in substantial practical and economic advantages. This paper analyses the performances and costs of such plants in scenarios with various amounts of wind generation, based on data for power demand and wind energy variability in the UK. In a scenario with 35% wind generation, overall emissions of CO2 could be reduced by 98–99%. The cost of abating CO2 emissions from the non-wind residual generation using the technique proposed in this paper would be less than 40% of the cost of using coal-fired power plants with integrated CCS.  相似文献   

20.
While the energy sector is the largest global contributor to greenhouse gas (GHG) emissions, the agriculture, forestry, and other land use (AFOLU) sector account for up to 80% of GHG emissions in the least developed countries (LDCs). Despite this, the nationally determined contributions (NDCs) of LDCs, including Nepal, focus primarily on climate mitigation in the energy sector. This paper introduces green growth—a way to foster economic growth while ensuring access to resources and environmental services—as an approach to improving climate policy coherence across sectors. Using Nepal as a case country, this study models the anticipated changes in resource use and GHG emissions between 2015 and 2030, that would result from implementing climate mitigation actions in Nepal's NDC. The model uses four different scenarios. They link NDC and policies across economic sectors and offer policy insights regarding (1) energy losses that could cost up to 10% of gross domestic product (GDP) by 2030, (2) protection of forest resources by reducing the use of biomass fuels from 465 million gigajoules (GJ) in 2015 to 195 million GJ in 2030, and (3) a significant reduction in GHG emissions by 2030 relative to the business-as-usual (BAU) case by greater use of electricity from hydropower rather than biomass. These policy insights are significant for Nepal and other LDCs as they seek an energy transition towards using more renewable energy and electricity.  相似文献   

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